David Stubbings, Museum Volunteer
Cambridge Museum of Technology
One of my favourite items is a mechanical calculator because it is very ‘hands on’, and working. You set the dials, turn the handle and get an answer. Addition on the machines is simple. To subtract you have to think a bit more, and think even more to multiply. And please explain division to me. What I find good is that it is easy to identify with people in history who used the machine. This then takes one into the history and reasons why they needed to calculate.
Part of what made Britain great is shipping and then steam. Behind the ship and the steam engine, is the physics – e.g. how temperature and pressure are related; how to navigate at sea. The physics involves maths, which involves calculations. Before the calculator, long multiplications and long division was done using logarithms. This involves looking up data in a table and is time consuming and error prone. Around the 1900s the calculating machine was in production and some larger companies had a department just for calculating – an office with calculating machines and
people trained to use them.
The two steam pumping engines in the Museum of Technology are made by the Hathorn Davey company who had their foundry and workshop in Leeds. Let’s say they employed 200 workers and the pay office want to know how much money and in what coins to get ready for pay day – they have calculations to do and they must be correct. The travailing crane above the steam engines is designed to lift a certain load. The design involves calculation that must be correct.
Things that are big and powerful start with mathematical calculations.